Well casing



July 24, 1928."

H. Y. CARSON WELL CASING Ori iBELfiled Aug. 18. 1922 v Harl y YCarson m v w m o M m 1 I v 4 1.. f Y. B

WITNESSES Patented July 24, 1928.

UNITED STATES v 1,678,280 PATENT OFFICE HARRY Y. PIPE COMPANY,

CARSON, OF BIRMINGHAM, ALABAMA, ASSIGNOR '10 AMERICAN CAST IRON OF BIRMINGHAM, ALABAMA, A CORPORATION.

WELL CASING.

Original application filed August 18, 1922, Serial No. 582,725. Divided and this application filed,

January 14, 1925.

This invention relates to well casings, and the present application is a division of an application filed by me August 18, 1922, Serial No. 582,725, for a patent on a well casing, wherein wasshown, described, and claimed, a well casing composed of sections having novel features for facilitating the introduction of said sections into a bored or drilled Welland also the means for connecting or jointing the samqtogether.

The present application is designed to cover the features of the well casing proper, and the object is to provide a cheaply and readily manufactured casing composedpf relatively short sections capable of being easily handled and formed of cast ron, said sections being of the bell and spigot type and having features that permit of their being easily and quickly connected together, and easily passed downwardly through the bore or well, provision being made to prevent the enlargement of said bell from engaging on stones, shoulders or other 1nequalities encountered during such passage.

A full and complete understanding of the invention may be obtained from a consideration of the following detailed description, taken in connection with the accompanying drawing forming a part of this specification, it being understood that while the drawing shows a practical form of the invention, the latter is not to be confined to strict conformity with the showing thereof, but may be changed or modified, so long as such changes or modifications mark no material departure from the salient features of the invention, as specifically pointed out in the appended claims.

In the drawing, in which similar reference characters designate corresponding parts throughout the several figures Figure 1 is aside elevation of one section of pipe constructed in accordance with the present invention, the same being shown connected to another section similarly formed and shown in section; and

Figure 2 is a detail, longitudinal section through the joint and drawn on a larger scale.

Referring to the drawing, there 1s shown a pipe section adapted to be formed of cast iron, steel, or other suitable cast metal, by any desired method, the length of the sections being such as to enable them to be Serial No. 2,331.

easily handled when coupling to form a well casing, and lowering the same into the bore or well, for which purpose they are especially intended.

Each section is provided with a bell end and a spigot end so shaped and proportioned that, when locked together, they ofler a minimum amount of enlargement and consequent obstruction which would ordinarily interfere with the free passage of the casing down a well, and likewise with the free upward passage of the casing, when it is desired to withdraw the same from the well; and in like manner, the interior of the easing is free from any material obstructions in the form of shoulders or projections which might interfere with the upward or downward passage of the working barrel, tubing, collars, etc.

Any suitable means may be employed for joining the several sections together without the use of poured metal, so that said joints will permit the sections to flex relative to each other without danger of leakage or seepage, to find its way down a well past projections or obstructions and to follow a more or less tortuous path where the well has not been bored plumb or regular, but no claim is made in the present application to the specific form of locking means shown.

The cast metal well casing under consideration is primarily adapted and intended for use in oil well service, though the same may be used with equal advantage in handling or piping such materials as sulphur, salt, water, etc.

In Figure 1 there is shown a portion of a well casing, including two pipe sections, each broken away, and one being shown in elevation and the other in longitudinal section. Each section is provided with a spigot end 1 and a bell end 2, the former being insorted into the latter in the usual manner of bell and spigot forms of pipe sections.

,The exterior diameter of the spigot is coextensive with the exterior diameter of the body or intermediate portion of the section, and is provided adjacent to its end with a circumferential enlargement 3, whose underside 4, when the sections are in normal position in a well, is in the form of a reverse curve to define a shoulder, and whose upper side 5 is f rmed on a l ght incl ne r p gradually mergin into the body of the see tion, so as to 0 or no abrupt shoulder or projection around the spigot end of the section; the extent of the circumferential enlargement thus produced being held at the minimum point.

The bell end 2, which is only slightly larger in diameter than the diameter of the spigot end enlargement 3, is joined to the body of the section by a gradual reduction in diameter in the form of a reverse curve 6, somewhat greater in diameter than the curve 4 of the spigot end, so as to offer the least resistance to the passage of the casing sections when being lowered into a well. The upper or terminal end of the bell 2 is tapered on its other face, as at 7, at an angle to coincide with the tapering face 5 of the adjacent spigot end, so that the bell and spigot together, when connected, form only a m 1nimum amount of enlargement or projectlon having gradually tapering upper and lower extremities, which will not engage inequalities in the bored well, either when the easing is being lowered into the same, or when being drawn out as sometimes becomes necessary either for using the casing in other wells or for other reasons. The comparatively short length of the sections, which are preferably made about five feet long, renders them especially advantageous for such removal from the well or insertion into the same, thus effecting a material saving in oil field operations, as the casing may be used repeatedly on other locations.

The hell 2 is provided with a socket 8 of greater diameter than the spigot and extending inwardly to a point adjacent to the exterior curve 6 of the bell, and there termlnating in an inwardly and downwardly tapering shoulder 9 comprising a seat for the inner or lower end of the spigot 1, and at a point substantially midway between the shoulder 9 and the outer free end of the bell, there are formed locking lugs 10 cast integrally with the section and on the in side of the socket. These lugs, preferably two in number, are located at diameterically opposite points and are adapted to coact with other lugs 11 formed on the exterior of the spigot end of the next adjacent pipe section to lock the two sections together by turning one member relative to the other, after the spigot is fully inserted in the bell, to bring the lug of the former to abut against the inner side of the lug of the socket, there being a suitable stop 12 on each of the lugs 11 to arrest such rotary movement at the proper point. Since, however, the structure, function and operation of the specific locking means forms the subject matter of the aforesaid application, no further description of the same is deemed necessary herein, as no claim is made to the same.

The free end of the spigot 1 is bevelled, as at '13 to conform to and to rest upon the seat or shoulder 9, at the base of the socket 8, said end having its bore or passageway rounded outwardly, as shown at 14, so as to obviate any shoulder which might interfere with the passage of tubing, rods, tools or other articles,

flexed with relation to the next adjacent sections, to a considerable extent, so as to permit the connected casin to follow the course of the well, even though the same may be out of plumb and irregular.

hen the sections are properly connected together, with the locking lugs in engagement, packing 15 is inserted into the mouth of the bell in surrounding relation to the spigot and filling the space between the same and the walls of the socket, the said packing being forced downwardly between the pairs of coacting locking lugs to engage with the internal seat or shoulder 9, as shown in Figure 2 of the drawing. The packing may consist of cement, asphalt, or other snnllar material, which may be readily employed for the purpose and applied in position as the sections are connected together and lowered into the well.

From the foregoing it will be seen that cheaply and easily constructed cast iron or other pipe sections may be produced for use as well casings, the said sections having means for locking the same together and permitting the joint to flex, and enable the pipe sections to follow the course of a well, whet-her straight or irregular, the exterior contour of the bell and spigot being such as to offer no obstruction to engage with inequalities or projections which may be encountered in the well.

It will also be seen that the interior construction in the bores of the sections is such as not to interfere with the introduction of well tubing carrying the working barrel at its lower end, and having the sections thereof joined together by threaded collars or couplings, the same readily sliding past the internal shoulder 3* formed in the casin sections in line with the exterior shoulder 3, said interior shoulders being suitably rounded to avoid such interference.

The well casing as herein shown and described is designed to be used in the place of wrought iron or steel well casings which are now in general use in oil fields, and which are subject to rapid deterioration, sometimes completely rusting out and per mitting the inflow of water, and sometimes requiring the entire replacement of the easmg.

What is claimed is 1. A well casing composed of pipe sections each having a bell and spigot end, said ed and merged into bell being of greater diameter than the pipe section, a circumferential enlargement 0 slightly less diameter than the bell formed on the'spigot in spaced relation to the end thereof and having its outer surface rounded and merged into the spigot, said enlargement being so spaced from the end of the spigot that when the bell and spigot are connected the enlargement is caused to overhang the bell end; each pipe section being gradually tapered in opposite directions at both ends of the bell and likewise gradually tapered from the enlargement toward the bell, so that the outer surfaces of the bell and enlargement are practically continuous when the spigot is fitted within the bell.

2. A well casing composed of cast iron pipe sections each having a bell end and a spigot end, the open end of the bell being exteriorly tapered and the opposite end of said bell merging into the body of the section, a circumferential enlargement formed on the spigot in spaced relation to the end thereof and having its outer surface roundthe spigot and adapted to be located adjacent to the mouth of the bell so as to overhang the same when the spigot and hell are connected, that wall of the circumferential enlargement remote from the end of the spigot being very gradually tapered to accord and-aline with the exte- -riorly tapered end of the bell to eliminate abrupt shoulders on the exterior of the connected sections.

3. A well casing composed of cast iron pipe'sections, each having a bell and spigot end for connecting the sections together, the bell enlargement having its inner end rounded and merged into the body of the section by a long compound curve, the outer end of the bell being exteriorly tapered and the end rounded, an enlargement formed on the spigot in spaced relation to the end thereof and adapted to overhang and coact with the bell, when the spigot is looked therein, to prevent the sections from catching when being lowered into a well, said spigot enlargement having its outer shoulder rounded and merged into the body of the spigot and adapted to lie close to the mouth of the bell when the sections are joined, the inner portion of said enlargement tapering back and merging into the body of the section and forming substantially a continuation of the external taper on the open end of the adjacent bell.

4. A well casing composed of pipe sections each having a bell and spigot end, said bell being of greater diameter than the pipe section; a circumferential enlargement o slightly less diameter than the bell formed on the spigot and having its outer surface rounded and merged into the spigot spaced from the end thereof; said enlargement being so spaced from the end of the spigotthat when the bell and spigot are connected the enlargement is adjacent the bell end, each pipe section being gradually tapered in op posite directions at both ends of the bell and likewise gradually tapered from the enlargement toward the bel so that the outer surfaces of the bell and enlargement are ractically continuous when the spigot is fitted within the bell; and complementary locking means projecting outwardly from the outer face of the spigot and inwardly from the inner surface of the bell and constructed and arranged to prevent longitudinal separation of the two sections of the well casing.

In testimony that I claim the foregoing as my own, I have hereto affixed my signature.

HARRY Y. CARSON. 

